Pavement ME Design – Impact of Local Calibration, Foundation Support, and Design and Reliability Thresholds

The Mechanistic-Empirical Pavement Design Guide (MEPDG) and the accompanying AASHTOWare Pavement ME Design software (hereafter referred to as the ME Design software) have been developed to replace the empirical AASHTO Pavement Design Guides. The MEPDG represents a quantum leap forward from the empirical pavement design procedures. As indicated in a survey of state agencies conducted in 2013, 43 agencies were evaluating the MEPDG, and 15 agencies planned to implement the new design procedure in the next two years. The implementation plans of these agencies include, among other elements, important steps for (1) conducting local calibration to account for differences in state practices, policies, and local conditions, and (2) selecting design thresholds and reliability levels for acceptable pavement designs. Without properly conducting these important implementation steps, the adoption of the MEPDG will not make the pavement design process “better.” In fact, it has been suggested that use of the globally calibrated ME Design software may potentially yield inaccurate asphalt pavement designs. Recognizing the importance of local calibration and selection of design thresholds and reliability levels, this study provides information and evidence to support the need for local calibration of the MEPDG and careful consideration of design thresholds and reliability levels in the implementation process. The results of this research effort are presented in two reports. A previous report was prepared to discuss the general approach to local calibration undertaken by state agencies and to summarize results of their local calibration efforts and recommendations for implementing the locally calibrated MEPDG. This (second) report presents results of a case study that compares pavement designs conducted with global and local calibration coefficients to illustrate the importance of conducting local calibration of the MEPDG in the implementation process. In addition, it provides results of sensitivity analyses that show the effect of performance criteria, reliability levels, and foundation support on pavement design. Key findings of this research effort are synthesized and recommendations are offered.

• Record URL:
  http://eng.auburn.edu/research/centers/ncat/files/technical-reports/rep17-08.pdf
• 
• Corporate Authors:

  National Center for Asphalt Technology

  Auburn University, 277 Technology Parkway
  Auburn, AL  United States  36830

  National Asphalt Pavement Association (NAPA)

  5100 Forbes Boulevard
  Lanham, Maryland  United States  20706
• Authors:
  • Tran, Nam
  • Robbins, Mary M
  • Rodezno, Carolina
  • Timm, David H
• Publication Date: 2017-9

Language

• English

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; References; Tables;
• Pagination: 53p

Subject/Index Terms

• TRT Terms: Calibration; Case studies; Mechanistic-empirical pavement design; Recommendations; Sensitivity analysis
• Identifier Terms: AASHTOWare (Software); Mechanistic-Empirical Pavement Design Guide
• Uncontrolled Terms: Local conditions
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01648015
• Record Type: Publication
• Report/Paper Numbers: NCAT Report 17-08
• Files: TRIS
• Created Date: Oct 3 2017 5:30PM